The State Department has reassigned its special envoy for closing the U.S. prison at Guantánamo Bay, Cuba, in another step away from one of President Barack Obama's first campaign promises.

Ambassador Daniel Fried is starting this week as the department's sanctions coordinator, according to an internal notice, focusing on governments like Iran and Syria.

And no one is replacing Fried as lead diplomat to persuade countries to resettle Guantánamo inmates approved for release. Instead, those responsibilities will now transfer to the department's legal office.

The reduced diplomatic effort comes as a military tribunal holds more hearings into the case of alleged 9/11 mastermind Khalid Sheik Mohammed and five other defendants who face almost 3,000 counts of murder. They could get the death penalty if convicted in a trial that is likely at least a year away. Most of this week's proceedings have focused on abstract pretrial legal issues.

Fried helped in the transfer of 40 detainees overseas during his four years as special envoy, assuming the post shortly after Obama first took office and promised to close the much-maligned prison within a year.

But Republican-led bills have since cut off funding to move detainees to foreign countries, and bringing them to the United States has been impossible since Congress blocked Obama's attempt in 2009 to try Mohammed and others accused of war crimes in a civilian court.

The Obama administration still hopes to close Guantánamo and send its remaining 166 inmates elsewhere, but officials say congressional restrictions have left diplomatic efforts severely hampered.

Despite signing last year's federal defense bill, the president criticized further provisions it included that regulated the detention, interrogation and prosecution of suspected terrorists. He called continued Guantánamo restrictions "unwise" and insisted federal courts can successfully prosecute terrorists.